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Related papers: Interpreting Hints for Lepton Flavor Universality …

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We explore the limits on lepton-flavor universality (LFU) violation in theories where the hierarchy problem is solved by means of a warped extra dimension. In those theories LFU violation, in fermion interaction with Kaluza-Klein modes of…

High Energy Physics - Phenomenology · Physics 2017-11-01 Eugenio Megias , Mariano Quiros , Lindber Salas

Lepton Flavor Universality Violation (LFUV) in $B$ decays in both neutral $b\rightarrow s l^+ l^-$ and charged $b\rightarrow cl\bar{\nu}_{l}$ processes observed in the ratios $R_{K^{(*)}}$ and $R_{D^{(*)}}$ is investigated in the framework…

High Energy Physics - Phenomenology · Physics 2022-02-16 Soumia Lebbal , Jamal Mimouni , Noureddine Mebarki

We present a new class of models of lepton flavor in the composite Higgs framework. Following the concept of minimality, they lead to a rich phenomenology in good agreement with the current experimental picture. Because of a unification of…

High Energy Physics - Phenomenology · Physics 2016-07-19 Adrian Carmona , Florian Goertz

We address the recent anomalies in semi-leptonic $B$-meson decays using a model of fermion masses based on the $U(2)$ flavor symmetry. The new contributions to $b \to s \ell \ell$ transitions arise due to a tree-level exchange of a…

High Energy Physics - Phenomenology · Physics 2016-01-20 Adam Falkowski , Marco Nardecchia , Robert Ziegler

In recent years, several observables associated to semileptonic $b \to s$ processes have been found to depart from their predicted values in the Standard Model, including a few tantalizing hints of lepton flavor universality violation. In…

High Energy Physics - Phenomenology · Physics 2019-02-20 Paulina Rocha-Moran , Avelino Vicente

We analyze the recent hints of lepton flavor universality violation in both charged-current and neutral-current rare decays of $B$-mesons in an $R$-parity violating supersymmetric scenario. Motivated by simplicity and minimality, we had…

High Energy Physics - Phenomenology · Physics 2020-08-05 Wolfgang Altmannshofer , P. S. Bhupal Dev , Amarjit Soni , Yicong Sui

The experimental measurements on flavour physics, in tension with Standard Model predictions, exhibit large sources of Lepton Flavour Universality violation. This note summarises an analysis of the effects of the global fits to the Wilson…

High Energy Physics - Phenomenology · Physics 2021-06-15 Jorge Alda , Jaume Guasch , Siannah Penaranda

We analyse the new physics implications of theoretically clean $b \to s$ observables in a model-independent approach and compare their coherence with the implications of other rare $B$-decays. A statistical comparison is done between the…

High Energy Physics - Phenomenology · Physics 2021-12-16 T. Hurth , F. Mahmoudi , D. Martinez Santos , S. Neshatpour

We propose renormalizable models of new physics that can explain various anomalies observed in decays of B-mesons to electron and muon pairs. The new physics states couple to linear combinations of Standard Model fermions, yielding a…

High Energy Physics - Phenomenology · Physics 2016-07-20 Ben Gripaios , M. Nardecchia , S. A. Renner

In the Standard Model (SM), the coupling of the electroweak gauge bosons to the leptons is lepton flavour universal. Tests of this property constitute sensitive probes for new physics models that violate lepton flavour universality. Recent…

High Energy Physics - Experiment · Physics 2018-07-01 Christoph Langenbruch

Motivated by the measurements of $b\to s\ell^+\ell^-$ transitions, including $R(K)$ and $R(K^*)$, we examine lepton flavour (universality) violation in $B$ decays and its connections to $\mu\to e\gamma$ in generic leptoquark models.…

High Energy Physics - Phenomenology · Physics 2018-02-07 Andreas Crivellin , Dario Mueller , Adrian Signer , Yannick Ulrich

The experimental measurements on flavour physics, in tension with Standard Model predictions, exhibit large sources of Lepton Flavour Universality violation. We perform an analysis of the effects of the global fits on the Wilson…

High Energy Physics - Phenomenology · Physics 2022-03-22 Jorge Alda , Jaume Guasch , Siannah Penaranda

In recent years, significant experimental indications that point towards Lepton Flavour Universality violating effects in B-decays, involving $b \to c \tau \nu$ and $b \to s \ell^+ \ell^-$ have been accumulated. A possible New Physics…

High Energy Physics - Phenomenology · Physics 2019-12-11 Sokratis Trifinopoulos

Several experiments reported hints for the violation of lepton flavor or lepton flavor universality in processes involving muons. Most prominently, there is the hint for a non-zero rate of the flavor violating Higgs decay $h \to \tau\mu$ at…

High Energy Physics - Phenomenology · Physics 2016-12-07 Wolfgang Altmannshofer , Marcela Carena , Andreas Crivellin

The LHCb collaboration has very recently released a new study of $B^+ \to K^{+} \ell^+ \ell^-$ and $B \to K^{*0} \ell^+ \ell^-$ ($\ell = e,\mu$) decays, testing lepton universality with unprecedented accuracy using the whole Run 1 and 2…

High Energy Physics - Phenomenology · Physics 2023-04-05 Marco Ciuchini , Marco Fedele , Enrico Franco , Ayan Paul , Luca Silvestrini , Mauro Valli

Recent results from the intensity frontier indicate the tantalizing possibility of violation in lepton flavour universality. In light of this we revisit the minimal phenomenological $Z'$ model taking in account both vectorial and…

High Energy Physics - Phenomenology · Physics 2023-01-03 Tirtha Sankar Ray , Avirup Shaw

The LHCb collaboration has recently presented their result on R_K = BR(B+ -> K+ mu+ mu-)/ BR(B+ -> K+ e+ e-) for the dilepton invariant mass bin m_{ll}^2 = 1-6 GeV^2 (l = mu, e). The measurement shows an intriguing 2.6 sigma deviation from…

High Energy Physics - Phenomenology · Physics 2015-06-22 Diptimoy Ghosh , Marco Nardecchia , S. A. Renner

We report on recent results obtained by the Belle II experiment related to searches for beyond-the-standard-model physics. The $B$ meson decay data sample used corresponds to an integrated luminosity of $L = 189$ fb$^{-1}$. In recent years,…

High Energy Physics - Experiment · Physics 2023-08-15 Roberta Volpe , Belle II Collaboration

We discuss the status of $b \to s \ell^+\ell^-$ decays in the post-$R_{K^{(*)}}$ era. The recent LHCb update of $R_K$ and $R_{K^*}$ measurements which are now compatible with the Standard Model, constrain new physics contributions to be…

High Energy Physics - Phenomenology · Physics 2023-10-10 T. Hurth , F. Mahmoudi , S. Neshatpour

We present a complete analysis of Lepton Flavor Universality (LFU) violations in leptonic $\tau$ decays in motivated models addressing the $B$-physics anomalies, based on the $SU(4)\times SU(3)\times SU(2)\times U(1)$ gauge group. We show…

High Energy Physics - Phenomenology · Physics 2022-01-19 Lukas Allwicher , Gino Isidori , Nudzeim Selimovic